VariTrac Installation
Caution: It is not recommended that 24Vac power be shared between controllers.
However, if controllers share a common transformer, polarity must be observed on 24Vac
connections on UCMs that share the same transformer.
Question: Would a VariTrac UCM set to address 25 communicate to a VariTrac? _____.
Why or why not? _______________________________________________________.
Question: Will the comm link function even though the electrician swapped polarity at
one of the Comm4 devices? ______. Why or why not? ________________________.
4. Install a zone sensor to VariTrac damper UCM, address #1. Use wire provided for both the
sensor/adjustable setpoint.
5. Install a digital zone sensor to VariTrac damper UCM, address #2. Use wire provided for both
the sensor/adjustable setpoint and 24Vac power.
Reference: VariTrac Installation Manual (VAV-SVN03A-EN), Pages 28 through 31
03- VariTrac Installation Workshop.doc
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